IV68447: GARBAGE COLLECTOR CRASHES WHEN GENERATING JAVACORE

PI37006: SHIP JAVA 6/26 SR8 FP3 + IV69354+IV69616+IV68447+IV70681 FOR WAS 8555
PI37009: SHIP JAVA 6/26 SR8 FP2 + IV68447+IV69354+IV66608+IV66375+IX90155+IV66944+IV66991+IV70681 for WAS 8554
PI37005: SHIP JAVA 7 SR8 FP10 +IV69419+IV68447+IV70681 FOR WAS 8555
PI37010: SHIP JAVA 6/26 SR8 FP2 + IV68447+IV69354+IV66608+IV66375+IX90155+IV66944+IV66991+IV70681
PI38186: Ship Java 6/26 SR8 FP3 +IV69354+IV69616+IV68447+IV70681 for WAS800x
PI42772:

APAR status

• Closed as program error.

Error description

• Error Message: A SIGSEGV/GPF is received when a user issues a
  user event to generate Javacore files.
  .
  Stack Trace: The native stack trace looks like
  this:incrementalScanCacheBySlot__20MM_ParallelScavengerFP22MM_En
  vironmentStandardcompleteScan__20MM_ParallelScavengerFP22MM_Envi
  ronmentStandardworkThreadGarbageCollect__20MM_ParallelScavengerF
  P22MM_EnvironmentStandardrun__23MM_ParallelScavengeTaskFP20MM_En
  vironmentModronslaveEntryPoint__21MM_ParallelDispatcherFP20MM_En
  vironmentModrondispatcher_thread_proc2__FP13J9PortLibraryPvj9sig
  _protectdispatcher_thread_procthread_wrapper
  .
  

Local fix

Problem summary

• The problem can occur when a Javacore file is generated while a
  garbage collection is in progress. Javacore generation queries
  the state of certain objects (e.g. threads), which may in turn
  update internal caches. If Javacore generation queries an object
  that the garbage collector is currently processing, these cache
  updates may lead to memory corruption.
  

Problem conclusion

• The JVM has been updated so that Javacore generation does not
  update internal caches.
  .
  This APAR will be fixed in the following Java Releases:
     6    SR17      (6.0.17.0)
     6 R1 SR8 FP4   (6.1.8.4)
     7    SR9       (7.0.9.0)
     7 R1 SR3       (7.1.3.0)
  .
  Contact your IBM Product's Service Team for these Service
  Refreshes and Fix Packs.
  For those running stand-alone, information about the Service
  Refreshes and Fix Packs can be found at:
             https://www.ibm.com/developerworks/java/jdk/
  

Temporary fix

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

Fix information

• Fixed component name

  J9 COMMON CODE

• Fixed component ID

  620700127

Applicable component levels

• R600 PSY

     UP

• R260 PSY

     UP

• R270 PSY

     UP